Partial band configuration for channel state information

ABSTRACT

Methods, systems, and devices for wireless communication are described that provide for the utilization of multiple partial bands used in the transmission of one or more channel state information (CSI) reference signals (CSI-RSs). The partial bands may be non-consecutive in the frequency domain, time domain, or a combination thereof and each of which may be precoder using a different precoder configuration. The time intervals, cycling granularity, and number of ports may vary between partial bands. Using RSs transmitted via the multiple partial bands, a user equipment (UE) may determine a channel state parameter for each partial band, which may be used for channel feedback.

CROSS REFERENCE

This present Application is a 371 national phase filing of InternationalPatent Application No. PCT/CN2017/097102 by Hao et al., entitled“PARTIAL BAND CONFIGURATION FOR CHANNEL STATE INFORMATION,” filed Aug.11, 2017, which claims priority to International Patent Application No.PCT/CN2017/083251 by Hao et al., entitled “PARTIAL BAND CONFIGURATIONFOR CHANNEL STATE INFORMATION,” filed May 5, 2017, each of which isassigned to the assignee hereof, and hereby incorporated by reference intheir entirety.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to partial band configuration for channel state information(CSI).

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems (e.g., a Long Term Evolution(LTE) system, or a New Radio (NR) system). A wireless multiple-accesscommunications system may include a number of base stations or accessnetwork nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

In some wireless communications systems, a base station may utilize anumber of precoders for transmitting signals to the UE. These precodersmay vary across frequency tones or resource blocks (RBs). For instance,the base station may utilize a first precoder for a first set of RBs(e.g., even numbered RBs) within a slot and a second precoder for asecond set of RBs (e.g., odd numbered RBs) within the slot. The use ofdifferent precoders across RBs within a given frequency bandwidth maymake it difficult to perform an accurate channel estimation across theentire bandwidth. Without an accurate channel estimation, the quality ofchannel feedback reports from the UE may be degraded, which maynegatively affect system performance.

SUMMARY

The described techniques relate to improved methods, systems, devices,or apparatuses that support partial band configuration for channel stateinformation (CSI). Generally, the described techniques provide for theutilization of a partial band configuration for transmission of one ormore CSI reference signals (CSI-RSs). Multiple partial bands may beconfigured for transmission of the CSI-RSs and may be non-consecutive inthe frequency domain, time domain, or combination thereof such that eachpartial band includes a set of frequency, time, or time-frequencyresources that do not overlap with frequency, time, or time-frequencyresources of another partial band. Each partial band may include a setof resource blocks (RBs) and may span a given time interval which mayvary with respect to other partial bands. The precoding configuration,cycling granularity, number of partial bands, and number of antennaports may also vary between partial bands.

A method of wireless communication is described. The method may includeidentifying a CSI-RS resource set with one CSI-RS resource fortransmission of multiple CSI-RSs to a user equipment (UE), precoding,according to a first partial band configuration, a first CSI-RS fortransmission over a first resource subset of the CSI-RS resourceassociated with the first non-consecutive partial band, precoding,according to a second partial band configuration, a second CSI-RS fortransmission over a second resource subset of the CSI-RS resourceassociated with the second non-consecutive partial band, andtransmitting, to the UE, the precoded first CSI-RS over the firstresource subset and the precoded second CSI-RS over the second resourcesubset.

An apparatus for wireless communication is described. The apparatus mayinclude means for identifying a CSI-RS resource set with one CSI-RSresource for transmission of multiple CSI-RSs to a UE, means forprecoding, according to a first partial band configuration, a firstCSI-RS for transmission over a first resource subset of the CSI-RSresource associated with the first non-consecutive partial band, meansfor precoding, according to a second partial band configuration, asecond CSI-RS for transmission over a second resource subset of theCSI-RS resource associated with the second non-consecutive partial band,and means for transmitting, to the UE, the precoded first CSI-RS overthe first resource subset and the precoded second CSI-RS over the secondresource subset.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to identify a CSI-RS resource setwith one CSI-RS resource for transmission of multiple CSI-RSs to a UE,precode, according to a first partial band configuration, a first CSI-RSfor transmission over a first resource subset of the CSI-RS resourceassociated with the first non-consecutive partial band, precode,according to a second partial band configuration, a second CSI-RS fortransmission over a second resource subset of the CSI-RS resourceassociated with the second non-consecutive partial band, and transmit,to the UE, the precoded first CSI-RS over the first resource subset andthe precoded second CSI-RS over the second resource subset.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to identify a CSI-RS resourceset with one CSI-RS resource for transmission of multiple CSI-RSs to aUE, precode, according to a first partial band configuration, a firstCSI-RS for transmission over a first resource subset of the CSI-RSresource associated with the first non-consecutive partial band,precode, according to a second partial band configuration, a secondCSI-RS for transmission over a second resource subset of the CSI-RSresource associated with the second non-consecutive partial band, andtransmit, to the UE, the precoded first CSI-RS over the first resourcesubset and the precoded second CSI-RS over the second resource subset.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CSI-RS resource may bepartitioned according to at least a first non-consecutive partial bandand a second non-consecutive partial band in a frequency domain, or timedomain, or a combination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first CSI-RS may beprecoded according to a first precoder configuration, and the secondCSI-RS may be precoded according to a second precoder configuration.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a total number ofprecoder configurations for transmission of the multiple CSI-RSs, wherethe CSI-RS resource may be partitioned into a plurality non-consecutivepartial bands based on the total number of precoder configurations.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving a channel feedbackmessage from the UE, where the channel feedback message may be computedbased on one or both of the first precoded CSI-RS and the secondprecoded CSI-RS.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the channel feedback messagemay indicate at least one of a precoding matrix indicator, a precodingtype indicator, a rank indicator, a channel quality indicator, or acombination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the transmission of theprecoded first CSI-RS over the first resource subset of the CSI-RSresource associated with the first non-consecutive partial band mayoccur at a different time than or at a same time as the transmission ofthe precoded second CSI-RS over the second resource subset of the CSI-RSresource associated with the second non-consecutive partial band.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first resource subset mayspan a time interval different from or the same as the second resourcesubset.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, a first cycling granularityfor precoding the first CSI-RS for the first non-consecutive partialband may be equal to or different from a second cycling granularity forprecoding the second CSI-RS for the second non-consecutive partial band.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first cycling granularitymay be a parameter of the first partial band configuration, and thesecond cycling granularity may be a parameter of the second partial bandconfiguration.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, transmitting the precodedfirst CSI-RS over the first resource subset may include transmitting theprecoded first CSI-RS using a part or all of the antenna ports in a setof antenna ports.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, transmitting the precodedsecond CSI-RS over the second resource subset may include transmittingthe precoded second CSI-RS using a part or all the antenna ports in theset of antenna ports.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for configuring the CSI-RS resource setwith multiple CSI-RS resources, where each CSI-RS resource may bepartitioned according to at least a first non-consecutive partial bandand a second non-consecutive partial band.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, at least two CSI-RS resourcesmay be different by at least a number of partial bands, a time durationfor each partial band, a cycling granularity for each partial band, anumber of CSI-RS ports for each partial band, precoder used for eachpartial band, or any combination thereof.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting a CSI-RS resource setconfiguration to the UE, where the CSI-RS resource set configurationincludes at least one of a number of CSI-RS resources of the CSI-RSresource set, a number of partial bands in each CSI-RS resource, a timeduration for each partial band, a cycling granularity for each partialband, a number of CSI-RS ports for each partial band, or a combinationthereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the configuration may beincluded in a radio resource control (RRC) message, medium accesscontrol (MAC) channel element (CE), or in downlink control information(DCI).

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the channel feedback messagemay indicate at least one of one or more CSI-RS resource indication(CRI), a precoding matrix indicator, a precoding type indicator, a rankindicator, a channel quality indicator, or a combination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the transmission the firstpartial band configuration and the second partial band configuration maybe individually or jointly encoded in DCI.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, a format of the DCI maycorrespond to one of a special DCI format or a CSI-RS DCI format.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the DCI may be one ofUE-specific or group-specific.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving a channel feedbackmessage from the UE, where the channel feedback message may be computedbased on at least one of the CSI-RS resources of the CSI-RS resourceset.

A method of wireless communication is described. The method may includereceiving, from a base station, a first CSI-RS over a first resourcesubset of a CSI-RS resource associated with a first non-consecutivepartial band, where the first CSI-RS is precoded according to a firstpartial band configuration, receiving a second CSI-RS over a secondresource subset of the CSI-RS resource associated with a secondnon-consecutive partial band, where the second CSI-RS is precodedaccording to a second partial band configuration, determining, based onthe first and second CSI-RSs, a channel state parameter based on thefirst non-consecutive partial band and the second non-consecutivepartial band, and transmitting, to the base station, a feedback messagethat indicates the channel state parameter.

An apparatus for wireless communication is described. The apparatus mayinclude means for receiving, from a base station, a first CSI-RS over afirst resource subset of a CSI-RS resource associated with a firstnon-consecutive partial band, where the first CSI-RS is precodedaccording to a first partial band configuration, means for receiving asecond CSI-RS over a second resource subset of the CSI-RS resourceassociated with a second non-consecutive partial band, where the secondCSI-RS is precoded according to a second partial band configuration,means for determining, based on the first and second CSI-RSs, a channelstate parameter based on the first non-consecutive partial band and thesecond non-consecutive partial band, and means for transmitting, to thebase station, a feedback message that indicates the channel stateparameter.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive, from a base station, afirst CSI-RS over a first resource subset of a CSI-RS resourceassociated with a first non-consecutive partial band, where the firstCSI-RS is precoded according to a first partial band configuration,receive a second CSI-RS over a second resource subset of the CSI-RSresource associated with a second non-consecutive partial band, wherethe second CSI-RS is precoded according to a second partial bandconfiguration, determine, based on the first and second CSI-RSs, achannel state parameter based on the first non-consecutive partial bandand the second non-consecutive partial band, and transmit, to the basestation, a feedback message that indicates the channel state parameter.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to receive, from a basestation, a first CSI-RS over a first resource subset of a CSI-RSresource associated with a first non-consecutive partial band, where thefirst CSI-RS is precoded according to a first partial bandconfiguration, receive a second CSI-RS over a second resource subset ofthe CSI-RS resource associated with a second non-consecutive partialband, where the second CSI-RS is precoded according to a second partialband configuration, determine, based on the first and second CSI-RSs, achannel state parameter based on the first non-consecutive partial bandand the second non-consecutive partial band, and transmit, to the basestation, a feedback message that indicates the channel state parameter.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining the channel stateparameter may include determining one or more channel state parametersfor the CSI-RS resource corresponding to the first and secondnon-consecutive partial bands based on a channel estimation of the firstand second non-consecutive partial bands.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving, from the base station,an indication of one or both of the first partial band configuration orthe second partial band configuration.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the indication may be receivedvia an RRC message, MAC CE, or DCI.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first precoderconfiguration may indicate at least one of the first resource subset, afirst cycling granularity for the first non-consecutive partial band, afirst time interval for the first CSI-RS, a first number of portsassociated with transmission of the first CSI-RS, or a combinationthereof. In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the second precoderconfiguration may indicate at least one of the second resource subset, asecond cycling granularity for the second non-consecutive partial band,a second time interval for the second CSI-RS, a second number of portsassociated with transmission of the second CSI-RS, or a combinationthereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first cycling granularitymay indicate a number of consecutive RBs in a frequency domain, timedomain, or a combination thereof of the first resource subset. In someexamples of the method, apparatus, and non-transitory computer-readablemedium described above, the second cycling granularity may indicate anumber of consecutive RBs in a frequency domain, a time domain, or acombination thereof of the second resource subset.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for estimating a first effectivechannel for the first non-consecutive partial band based on a first setof RBs of the first resource subset. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forestimating a second effective channel for the second non-consecutivepartial band based on a second set of RBs of the second resource subset,where the second non-consecutive partial band includes a non-consecutivepartial band from the first non-consecutive partial band in a frequencydomain, time domain, or a combination thereof.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for selecting a CRI based on the firstand second effective channels, where the channel state parameter may bedetermined based on the CRI.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the channel state parametermay include at least one of a precoding matrix indicator, a precodingtype indicator, a rank indicator, a channel quality indicator, or acombination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, one or both of the first andsecond CSI-RS port to data precoder mappings may be based in part on aco-phase vector or Alamouti encoding associated with a set of resourceelements (REs) corresponding to a respective resource subset of thefirst resource subset and the second resource subset.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving, from the base station, acontrol message indicating that the first partial band configuration andthe second partial band configuration may have different configurationparameters.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, at least one configurationparameter of the first partial band configuration or the second partialband configuration may be received in an RRC message, MAC CE, or in DCI.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CSI-RS resource mayinclude one CSI-RS resource of a CSI-RS resource set.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving, from the base station,multiple CSI-RS resources from the CSI-RS resource set, where eachCSI-RS resource may be partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial band.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, at least two CSI-RS resourcesmay be different by at least a number of partial bands, a time durationfor each partial band, a cycling granularity for each partial band, anumber of CSI-RS ports for each partial band, precoder used for eachpartial band, or any combination thereof.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving, from the base station, aCSI-RS resource set configuration, where the CSI-RS resource setconfiguration includes at least one of a number of CSI-RS resources ofthe CSI-RS resource set, a number of partial bands in each CSI-RSresource, a time duration for each partial band, a cycling granularityfor each partial band, a number of CSI-RS ports for each partial band,or a combination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the configuration may beincluded in a RRC message, MAC CE, or in DCI.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationthat supports partial band configuration for channel state information(CSI) in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports partial band configuration for CSI in accordance with aspectsof the present disclosure.

FIG. 3 illustrates an example of a reference signal (RS) scheme thatsupports partial band configuration for CSI in accordance with aspectsof the present disclosure.

FIG. 4 illustrates an example of a process flow that supports partialband configuration for CSI in accordance with aspects of the presentdisclosure.

FIGS. 5 through 7 show block diagrams of a device that supports partialband configuration for CSI in accordance with aspects of the presentdisclosure.

FIG. 8 illustrates a block diagram of a system including a base stationthat supports partial band configuration for CSI in accordance withaspects of the present disclosure.

FIGS. 9 through 11 show block diagrams of a device that supports partialband configuration for CSI in accordance with aspects of the presentdisclosure.

FIG. 12 illustrates a block diagram of a system including a userequipment (UE) that supports partial band configuration for CSI inaccordance with aspects of the present disclosure.

FIGS. 13 and 14 illustrate methods for partial band configuration forCSI in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

A base station in a wireless communications system may transmitreference signals (RSs) to a user equipment (UE) or a group of UEs. Onesuch reference signal is a channel state information (CSI) RS (CSI-RS),which may be used by a UE to determine channel conditions or estimate aneffective channel used for communication with the base station. In somecases, the base station may precode sets of frequency resources in agiven time slot using different precoding configurations fortransmission of one or more CSI-RSs. This use of different precodingconfigurations may complicate the process of obtaining an accuratewideband channel quality across the frequency bandwidth used fortransmission.

Techniques described herein may employ the use of multiple partial bandsfor transmission of one or more CSI-RSs. A partial band may refer to asubset of frequency tones within a carrier or channel (e.g., as definedin the frequency domain by a set of resource blocks). A non-sequentialor non-consecutive partial band may refer to a partial band defined by aset of resource blocks of a carrier or channel that are non-contiguous.The partial bands may be non-contiguous or non-consecutive in thefrequency domain, time domain, or a combination thereof, and may beconfigured by a base station or other network entity. A partial bandconfiguration may refer to a set of parameters, such as cyclinggranularity, time duration, and resources, defined for a partial band.Each of the multiple partial bands may be associated with a differentpartial band configuration. In some instances, at least some parametersof the parameters of a partial band configuration may be the same fortwo or more different partial bands. The base station may utilize themultiple partial bands to transmit one or more CSI-RSs to a UE. Afterreceiving the one or more CSI-RSs, the UE may determine a channel stateparameter such as channel quality indicator (CQI), rank indicator (RI),CSI resource indicator (CRT), among others for each of the one or moreCSI-RSs. The channel state parameter may then be transmitted to the basestation in a feedback message. In some cases, the channel stateparameter for each partial band may be averaged and the average channelstate parameter may be reported to the base station. Such techniques mayallow for a more accurate wideband channel estimation.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects are then described with RSschemes and process flows. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to partial bandconfiguration for CSI.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE), LTE-Advanced (LTE-A) network, ora New Radio (NR) network. In some cases, wireless communications system100 may support enhanced broadband communications, ultra-reliable (i.e.,mission critical) communications, low latency communications, andcommunications with low-cost and low-complexity devices.

Wireless communications system 100 may support efficient techniques fora base station 105 to utilize partial bands for signal transmission.Such techniques may allow a UE 115 to determine accurate CSI with lowsignaling overhead. The base station may configure multiplenon-consecutive partial bands (e.g., in a comb structure) and differentprecoders may be utilized on different frequency and time resources. Byutilizing partial band configurations, a UE 115 may perform channelestimation for a precoded channel in each partial band. UE 115 may alsocalculate a spectral efficiency according to resource element (RE)-levelco-phase cycling. Based on the channel estimations for each partialband, the UE 115 may determine respective channel feedback parameters(e.g., CRI, RI, CQI) and report such parameters to the base station 105.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communications system 100 mayinclude uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions, from a base station 105 to a UE 115. Controlinformation and data may be multiplexed on an uplink channel or downlinkaccording to various techniques. Control information and data may bemultiplexed on a downlink channel, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, the controlinformation transmitted during a transmission time interval (TTI) of adownlink channel may be distributed between different control regions ina cascaded manner (e.g., between a common control region and one or moreUE-specific control regions).

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a user agent, a mobileclient, a client, or some other suitable terminology. A UE 115 may alsobe a cellular phone, a personal digital assistant (PDA), a wirelessmodem, a wireless communication device, a handheld device, a tabletcomputer, a laptop computer, a cordless phone, a personal electronicdevice, a handheld device, a personal computer, a wireless local loop(WLL) station, an Internet of Things (IoT) device, an Internet ofEverything (IoE) device, a machine type communication (MTC) device, anappliance, an automobile, or the like.

In some cases, a UE 115 may also be able to communicate directly withother UEs (e.g., using a peer-to-peer (P2P) or device-to-device (D2D)protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the coverage area 110 of a cell. Other UEs115 in such a group may be outside the coverage area 110 of a cell, orotherwise unable to receive transmissions from a base station 105. Insome cases, groups of UEs 115 communicating via D2D communications mayutilize a one-to-many (1:M) system in which each UE 115 transmits toevery other UE 115 in the group. In some cases, a base station 105facilitates the scheduling of resources for D2D communications. In othercases, D2D communications are carried out independent of a base station105.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines, i.e., Machine-to-Machine (M2M) communication. M2M or MTC mayrefer to data communication technologies that allow devices tocommunicate with one another or a base station without humanintervention. For example, M2M or MTC may refer to communications fromdevices that integrate sensors or meters to measure or captureinformation and relay that information to a central server orapplication program that can make use of the information or present theinformation to humans interacting with the program or application. SomeUEs 115 may be designed to collect information or enable automatedbehavior of machines. Examples of applications for MTC devices includesmart metering, inventory monitoring, water level monitoring, equipmentmonitoring, healthcare monitoring, wildlife monitoring, weather andgeological event monitoring, fleet management and tracking, remotesecurity sensing, physical access control, and transaction-basedbusiness charging.

In some cases, an MTC device may operate using half-duplex (one-way)communications at a reduced peak rate. MTC devices may also beconfigured to enter a power saving “deep sleep” mode when not engagingin active communications. In some cases, MTC or IoT devices may bedesigned to support mission critical functions and wirelesscommunications system may be configured to provide ultra-reliablecommunications for these functions.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1, etc.). Base stations105 may communicate with one another over backhaul links 134 (e.g., X2,etc.) either directly or indirectly (e.g., through core network 130).Base stations 105 may perform radio configuration and scheduling forcommunication with UEs 115, or may operate under the control of a basestation controller (not shown). In some examples, base stations 105 maybe macro cells, small cells, hot spots, or the like. Base stations 105may also be referred to as evolved NodeBs (eNBs) 105.

A base station 105 may be connected by an S1 interface to the corenetwork 130. The core network may be an evolved packet core (EPC), whichmay include at least one mobility management entity (MME), at least oneserving gateway (S-GW), and at least one Packet Data Network (PDN)gateway (P-GW). The MME may be the control node that processes thesignaling between the UE 115 and the EPC. All user Internet Protocol(IP) packets may be transferred through the S-GW, which itself may beconnected to the P-GW. The P-GW may provide IP address allocation aswell as other functions. The P-GW may be connected to the networkoperators IP services. The operators IP services may include theInternet, the Intranet, an IP Multimedia Subsystem (IMS), and aPacket-Switched (PS) Streaming Service.

Wireless communications system 100 may operate in an ultra-highfrequency (UHF) frequency region using frequency bands from 700 MHz to2600 MHz (2.6 GHz), although some networks (e.g., a wireless local areanetwork (WLAN)) may use frequencies as high as 4 GHz. This region mayalso be known as the decimeter band, since the wavelengths range fromapproximately one decimeter to one meter in length. UHF waves maypropagate mainly by line of sight, and may be blocked by buildings andenvironmental features. However, the waves may penetrate wallssufficiently to provide service to UEs 115 located indoors. Transmissionof UHF waves is characterized by smaller antennas and shorter range(e.g., less than 100 km) compared to transmission using the smallerfrequencies (and longer waves) of the high frequency (HF) or very highfrequency (VHF) portion of the spectrum. In some cases, wirelesscommunications system 100 may also utilize extremely high frequency(EHF) portions of the spectrum (e.g., from 30 GHz to 300 GHz). Thisregion may also be known as the millimeter band, since the wavelengthsrange from approximately one millimeter to one centimeter in length.Thus, EHF antennas may be even smaller and more closely spaced than UHFantennas. In some cases, this may facilitate use of antenna arrayswithin a UE 115 (e.g., for directional beamforming). However, EHFtransmissions may be subject to even greater atmospheric attenuation andshorter range than UHF transmissions.

Thus, wireless communications system 100 may support millimeter wave(mmW) communications between UEs 115 and base stations 105. Devicesoperating in mmW or EHF bands may have multiple antennas to allowbeamforming. That is, a base station 105 may use multiple antennas orantenna arrays to conduct beamforming operations for directionalcommunications with a UE 115. Beamforming (which may also be referred toas spatial filtering or directional transmission) is a signal processingtechnique that may be used at a transmitter (e.g., a base station 105)to shape and/or steer an overall antenna beam in the direction of atarget receiver (e.g., a UE 115). This may be achieved by combiningelements in an antenna array in such a way that transmitted signals atparticular angles experience constructive interference while othersexperience destructive interference.

Multiple-input multiple-output (MIMO) wireless systems use atransmission scheme between a transmitter (e.g., a base station 105) anda receiver (e.g., a UE 115), where both transmitter and receiver areequipped with multiple antennas. Some portions of wirelesscommunications system 100 may use beamforming. For example, base station105 may have an antenna array with a number of rows and columns ofantenna ports that the base station 105 may use for beamforming in itscommunication with UE 115. Signals may be transmitted multiple times indifferent directions (e.g., each transmission may be beamformeddifferently). A mmW receiver (e.g., a UE 115) may try multiple beams(e.g., antenna subarrays) while receiving the synchronization signals.

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support beamformingor MIMO operation. One or more base station antennas or antenna arraysmay be collocated at an antenna assembly, such as an antenna tower. Insome cases, antennas or antenna arrays associated with a base station105 may be located in diverse geographic locations. A base station 105may multiple use antennas or antenna arrays to conduct beamformingoperations for directional communications with a UE 115.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use Hybrid ARQ (HARQ) to provideretransmission at the MAC layer to improve link efficiency. In thecontrol plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a network device (e.g., a base station105), or core network 130 supporting radio bearers for user plane data.At the Physical (PHY) layer, transport channels may be mapped tophysical channels.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including: wider bandwidth, shorter symbol duration, shorterTTIs, and modified control channel configuration. In some cases, an eCCmay be associated with a carrier aggregation configuration or a dualconnectivity configuration (e.g., when multiple serving cells have asuboptimal or non-ideal backhaul link). An eCC may also be configuredfor use in unlicensed spectrum or shared spectrum (where more than oneoperator is allowed to use the spectrum). An eCC characterized by widebandwidth may include one or more segments that may be utilized by UEs115 that are not capable of monitoring the whole bandwidth or prefer touse a limited bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration isassociated with increased subcarrier spacing. A device, such as a UE 115or base station 105, utilizing eCCs may transmit wideband signals (e.g.,20, 40, 60, 80 MHz, etc.) at reduced symbol durations (e.g., 16.67microseconds). A TTI in eCC may consist of one or multiple symbols. Insome cases, the TTI duration (that is, the number of symbols in a TTI)may be variable.

A shared radio frequency spectrum band may be utilized in an NR sharedspectrum system. For example, an NR shared spectrum may utilize anycombination of licensed, shared, and unlicensed spectrums, among others.The flexibility of eCC symbol duration and subcarrier spacing may allowfor the use of eCC across multiple spectrums. In some examples, NRshared spectrum may increase spectrum utilization and spectralefficiency, specifically through dynamic vertical (e.g., acrossfrequency) and horizontal (e.g., across time) sharing of resources.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ LTE License AssistedAccess (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NRtechnology in an unlicensed band such as the 5 GHz Industrial,Scientific, and Medical (ISM) band. When operating in unlicensed radiofrequency spectrum bands, wireless devices such as base stations 105 andUEs 115 may employ listen-before-talk (LBT) procedures to ensure thechannel is clear before transmitting data. In some cases, operations inunlicensed bands may be based on a CA configuration in conjunction withCCs operating in a licensed band. Operations in unlicensed spectrum mayinclude downlink transmissions, uplink transmissions, or both. Duplexingin unlicensed spectrum may be based on frequency division duplexing(FDD), time division duplexing (TDD) or a combination of both.

A base station 105 may utilize a number of data precoders fortransmitting signals to one or multiple UEs 115. For example, the numberof precoders may correspond to the number of CSI-RSs configured by basestation 105. In some cases, base station 105 may utilize precodercycling by varying the data precoders across different sets of frequencytones (e.g., resource blocks (RBs)) within a given time interval (e.g.,a slot, mini slot, orthogonal frequency division multiplexing (OFDM)symbol). For instance, base station 105 may utilize a first precoder fora first set of RBs (e.g., even numbered RBs) within a given slot and asecond precoder for a second set of RBs (e.g., odd numbered RBs) withinthe given slot. In some examples, base station 105 may transmit anon-precoded CSI-RS. A UE 115 may measure the non-precoded (i.e., ClassA) CSI-RS or precoded (i.e., Class B) CSI-RS received and report thebest CRI along with an associated RI, spectral efficiency, or CQI backto base station 105. Because the precoder may vary across RBs forprecoded CSI-RSs within a frequency bandwidth, the UE 115 may be unableto perform an accurate channel estimation across the bandwidth.

FIG. 2 illustrates an example of a wireless communications system 200that supports partial band configuration for CSI in accordance withvarious aspects of the present disclosure. In some examples, wirelesscommunications system 200 may implement aspects of wirelesscommunications system 100. Wireless communications system 200 includesbase station 105-a and UE 115-a, which may be examples of a base station105 and UE 115 described with reference to FIG. 1.

As shown, base station 105-a and UE 115-a may exchange messages bywirelessly communicating over communication link 205, which may be anexample of communication link 125 as described with reference to FIG. 1.Communication link 205 may be associated with a given radio accessnetwork (RAN) that supports operations over one or more bands, each ofwhich may include multiple carriers. In some examples, base station105-a may include one or more physical antennas 210 that may be used forcommunicating with UE 115-a. Signals may be modulated onto frequencyresources (e.g., tones) and time resources (e.g., symbols andtransmitted to a UE 115-a using the one or more physical antennas 210.

According to some aspects, base station 105-a may also include one ormore antenna ports 215-a through 215-n, which may be used for differenttransit diversity schemes or spatial multiplexing schemes. In somecases, the number of antenna ports 215 may be different from the numberof physical antennas 210, though in other examples, the number ofantenna ports 215 and physical antennas 210 may be the same. Eachantenna port may be associated with a different RS sequencecorresponding to different RSs and may support transmission ofUE-specific signals or common signals (e.g., RSs transmitted to multipleUEs 115). For instance, antenna ports 215-a, 215-b, and 215-c maysupport UE-specific signals (e.g., demodulation RS (DMRS)), whileantenna ports 215-d through 215-n may support CSI-RSs.

In the example of FIG. 2, base station 105-a may transmit one or moreRSs to UE 115-a according to an RS scheme. For instance, base station105-a may configure multiple partial bands for transmission of one ormore CSI-RSs. The partial bands may be non-consecutive in the frequencydomain, time domain, or a combination thereof and may be transmitted tothe UE 115-a via communication link 205. Each partial band may beconfigured according to a respective partial band configuration, whichmay include a time duration (e.g., a slot, a mini slot, a symbol) fortransmission of the CSI-RS in the partial band. The partial bandconfiguration may also include a cycling granularity that indicates thenumber of RBs over which the CSI-RS is transmitted (e.g., 1, 2, 3, RBs).The partial band configuration may also indicate the total number ofpartial bands configured by base station 105-a, which may be based onthe number of candidate precoders used by base station 105-a, and anumber of CSI-RS ports for each partial band (e.g., based on differentcoding levels or associated antenna ports 215). In some cases, basestation 105-a may utilize a different precoder for one or more partialbands such that the precoding configuration for a CSI-RS of a firstpartial band is different from the precoding configuration for a CSI-RSof a second partial band. In some examples, base station 105-a maydetermine the precoder type (e.g., Class B) for precoding, which may beselected from a set of precoders or precoder configurations or may beindicated by another network entity (e.g., a core network 130).Alternatively, the precoding configuration may be based on reportingfrom UE 115-a (e.g., in a hybrid CSI-RS mode).

FIG. 3 illustrates an example of an RS scheme 300 that supports partialband configuration for CSI in accordance with various aspects of thepresent disclosure. In some examples, RS scheme 300 may implementaspects of wireless communications systems 100 and/or 200 as describedwith reference to FIGS. 1 and 2. RS scheme 300 may include multiplepartial bands 301, which may be configured by a network node such as abase station 105 as described with reference to FIGS. 1 and 2. While twopartial bands 301-a and 301-b are shown, the number of partial bands 301may vary (e.g., 1, 2, 3, 5, 8, 9).

Each partial band 301 may have varying cycling granularities in the timedomain or the frequency domain or a combination thereof. The cyclinggranularity in the frequency domain may indicate the number ofconsecutive RBs 330 (e.g., 1, 2, 3, 5, or 9 RBs) within each partialband 301. As shown in the example of FIG. 3, partial bands 301-a and301-b may each have a cycling granularity of 1 RB in the frequencydomain, and each partial band 301 may span every other RB 330 in thefrequency domain. In this example, partial band 301-a may span oddnumbered RBs 330-a and 330-c, while partial band 301-b may span evennumbered RBs 330-b and 330-d. In some cases, each partial band 301 mayspan multiple sets of consecutive RBs 330.

In the time domain, each partial band 301 may span a given time interval305 within time duration 310. The given time intervals 305 may be anytime period (e.g., slot, mini slot, symbol, subframe, etc.). In thisexample, both of partial bands 301-a and 301-b may be configured to spantime interval 305-a (e.g., a slot), skip time intervals 305-b and 305-c,and repeat in time interval 305-d. Though shown spanning time intervals305-a and 305-d, partial bands 301 may span multiple sets of timeintervals 305 or each partial band 301 may span a different timeinterval 305 and may be associated with a different cycling granularityin the time domain. Each partial band 301 may have a cycling granularityin both the time domain and the frequency domain.

In some examples, if the cycling granularity in the time domain is 1slot, there may be no cycling or partial bands in the time domain for RSscheme 300, and if the cycling granularity in the frequency domain is 1RB, a base station 105 may configure 2 partial bands such that a firstpartial band spans even RBs and a second partial band spans odd RBs(e.g., partial bands 301-a and 301-b). Additionally or alternatively, ifthe cycling granularity is half a slot (e.g., a mini-slot) in the timedomain and the cycling granularity in the frequency domain is the wholeband, the base station 105 may configure partial band 301-a in a firsthalf of a slot (e.g., first mini-slot) and partial band 301-b in asecond half of the slot (e.g., second mini-slot)). Further, if the timeinterval is half a slot (e.g., a mini-slot) in the time domain and thecycling granularity in the frequency domain is 1 RB, the base station105 may configure four partial bands such that the first partial bandspans even RBs in a first mini-slot, a second partial band spans odd RBsin the first mini-slot, a third partial band spans even RBs in a secondmini-slot, and a fourth partial band spans odd RBs in the secondmini-slot.

Each partial band 301 may be configured for transmission of a CSI-RSduring respective time intervals 305. Further, each partial band 301 maybe configured to utilize a number of antenna ports for transmission ofthe CSI-RSs. For example, two antenna ports 315-a and 315-b may be usedfor the partial band 301-a, and two antenna ports 320-a and 320-b may beused for the partial band 301-b. While two antenna ports are shown foreach partial band 301 in FIG. 3, the number of antenna ports may varyfor each partial band 301. For instance, the number of antenna ports maybe 2, 4, 5, 7, 8, etc.

In some cases, the number of partial bands 301 may correspond to thenumber of precoders utilized for precoding (e.g., performed by basestation 105 or other network entity). In the example of FIG. 3, twoprecoders may be utilized, one for partial band 301-a and another forpartial band 305-b. Due to the varying precoders used for each of thepartial bands, the two partial bands 301 may be precoded according torespective precoding configurations. For example, partial bands 301-aand 301-b may each utilize different precoders to reflect the precodercycling behavior. An RB level beam cycling may be configured for each ofpartial bands 301-a and 301-b based on parameters that correspond to agiven partial band configuration (Partial Band 0, Partial Band 1, etc.),as indicated in example configurations of Tables 1 or 2 below.

TABLE 1 Resource Number Precoder Cycling Block Time of CSI- ofGranularity Set Interval RS Ports CSI-RS Partial Band 0 1 RB 0, 4, 8, .. . 1 slot 2 $\begin{bmatrix}b_{0} & 0 \\0 & b_{0}\end{bmatrix}\quad$ Partial Band 1 1 RB 1, 5, 9, . . . 1 slot 2$\begin{bmatrix}b_{1} & 0 \\0 & b_{1}\end{bmatrix}\quad$ Partial Band 2 1 RB 2, 6, 10, . . . 1 slot 2$\begin{bmatrix}b_{2} & 0 \\0 & b_{2}\end{bmatrix}\quad$ Partial Band 3 1 RB 3, 7, 11, . . . 1 slot 2$\begin{bmatrix}b_{3} & 0 \\0 & b_{3}\end{bmatrix}\quad$

As shown in Table 1, Partial Bands 0, 1, 2, and 3 may be each configuredwith a set of parameters (cycling granularity, RB set, time interval,etc.). For example, although each of Partial Bands 0, 1, 2, and 3 have asame time interval (1 slot), Partial Band 0 may be configured with RBset {0, 4, 8, . . . } while Partial Band 1 may be configured with adifferent RB set {1, 5, 9, . . . }. Further, each partial band mayutilize different beam vectors (b_(n)) for precoding of the CSI-RS, asindicated in Table 1. For instance, although each of Partial Bands 0, 1,2, and 3 have a same RB level cycling granularity (1 RB), different beamvectors may be utilized for different Partial Bands. In this example, 4different beam vectors (b₀, b₁, b₂, b₃) are configured, one for each ofPartial Bands 0, 1, 2, and 3.

TABLE 2 Resource Number Precoder Cycling Block Time of CSI- ofGranularity Set Interval RS Ports CSI-RS Partial Band 0 2 RBs [0, 1],[8, 9], [16, 17], . . . 1 slot 2 $\begin{bmatrix}b_{0} & 0 \\0 & b_{0}\end{bmatrix}\quad$ Partial Band 1 2 RBs [2, 3], [10, 11], [18, 19], . .. 1 slot 2 $\begin{bmatrix}b_{1} & 0 \\0 & b_{1}\end{bmatrix}\quad$ Partial Band 2 2 RBs [4, 5], [12, 13], [20, 21], . .. 1 slot 2 $\begin{bmatrix}b_{2} & 0 \\0 & b_{2}\end{bmatrix}\quad$ Partial Band 3 2 RBs [6, 7], [14, 15], [22, 23], . .. 1 slot 2 $\begin{bmatrix}b_{3} & 0 \\0 & b_{3}\end{bmatrix}\quad$

Similar to Table 1, Table 2 shows various configuration parameters forPartial Bands 0, 1, 2, and 3 (e.g., such as cycling granularity, RB set,time interval, etc.). In Table 2, although each of Partial Bands 0, 1,2, and 3 may have a same time interval (1 slot), each of the PartialBands 0, 1, 2, and 3 may be configured with different RB sets due to acycling granularity of 2 RBs in the frequency domain. For instance,Partial Band 1 may be configured with RB set {[0,1], [8,9], [16,17], . .. }, and Partial Band 3 may be configured with RB set {[6,7], [14,15],[22,23], . . . }. Further, each partial band may utilize different beamvectors (b_(n)) for precoding of the CSI-RS, as indicated in Table 2.For instance, although each of Partial Bands 0, 1, 2, and 3 may have asame RB level cycling granularity (2 RBs), different beam vectors (b₀,b₁, b₂, b₃) may be utilized for different Partial Bands.

In some cases, a base station 105 may configure K>1 CSI-RS resources.The partial band configuration in the K CSI-RS resources may bedifferent in terms of the number of partial bands, the cyclinggranularity in the frequency or time domain, the number of CSI-RS ports,the precoder of CSI-RS, or any combination thereof. For instance, a basestation 105 may configure two CSI-RS resources, the partial bandconfiguration for the first CSI-RS resource may be configured based onTable 1, while the partial band configuration for the second CSI-RSresource may be configured based on a Table 2. In this case, a partialband configuration for the first CSI-RS resource may be Partial Band 1of Table 1 having a cycling granularity of 1 RB in the frequency domain,and a partial band configuration for the second CSI-RS resource may bePartial Band 2 of Table 2 having a cycling granularity of 2 RBs in thefrequency domain.

The precoding configuration may be based on the data precoder used toprecode the RS for transmission using a given partial band. A dataprecoder (W) may be defined as the product of a beam matrix and aco-phase vector (e.g., W=W1× W2). The beam matrix (W1) may be given as

$\begin{bmatrix}b_{n} & 0 \\0 & b_{n}\end{bmatrix},$

where n is the beam vector index. The co-phase vector (W2) may be anelement of:

$\begin{Bmatrix}{\begin{bmatrix}1 \\1\end{bmatrix},} & {\begin{bmatrix}1 \\{- 1}\end{bmatrix},} & {\begin{bmatrix}1 \\j\end{bmatrix},} & \begin{bmatrix}1 \\{- j}\end{bmatrix}\end{Bmatrix}.$

In the examples shown in Table 1 and Table 2, the cycling precoders foreach partial band may be determined based on W1. In some other cases,the cycling precoders for each partial band may be determined based onW=W1×W2.

In some examples, base station 105 may signal the partial bandconfiguration in a dynamic or semi-static manner. For instance, theCSI-RS may be signaled by the base station 105 (e.g., to a set of UEs115) dynamically through downlink control information (DCI). In somecases, a DCI format designated for partial band configurations may beutilized for indicating one or more partial band configurationparameters. Additionally or alternatively, the configuration parametersmay be embedded in a DCI message according to a DCI format for CSI-RS.The DCI may be UE-specific or group specific.

In some cases, the CSI-RS may be semi-statically configured (e.g.,through RRC signaling). In order to reduce signaling overhead, the basestation 105 may define a set of partial band configurations (e.g., asshown in Table 3 below). The set of partial band configurations mayinclude multiple parameters, such as the number of partial bands(N_(PB)), the cycling granularity in the frequency domain (N_(cyc)), thenumber of CSI-RS ports for each partial band (N_(p)), and the cyclinggranularity in the time domain (i.e., time interval, T_(slot)). In someexamples, the base station 105 may utilize multiple bits (e.g., 2, 3, 4,or 7 bits) to signal the group and partial band configuration. Formultiple CSI-RS resources, the precoders and parameters may differacross different CSI-RS resources.

TABLE 3 N_(PB) N_(cyc) N_(p) T_(slot) Group 0 1 N/A 2 1 Group 1 2 N/A 40.5 Group 2 2 1 4 1 Group 3 2 2 4 1 Group 4 4 2 2 0.5 Group 5 4 2 4 0.5Group 6 4 1 2 1 Group 7 4 1 4 1

In some examples, Group 0 may indicate the bandwidth is reserved for asingle precoder and that no RB-level or partial slot cycling isutilized. Group 1 may indicate partial slot beam pair cycling, and Group2 may indicate RB-level beam pair cycling. Group 3 may indicate twoRB-level beam pair cycling. Group 4 may indicate two RB-level pluspartial slot beam cycling. Group 5 may indicate two RB-level pluspartial slot beam pair cycling. Group 6 may indicate RB-level beamcycling. Group 7 may indicate RB-level beam pair cycling.

FIG. 4 illustrates an example of a process flow 400 that supportspartial band configuration for channel state information in accordancewith various aspects of the present disclosure. In some examples,process flow 400 may implement aspects of wireless communications system100 and/or 200. Process flow 400 illustrates aspects of techniqueperformed by a base station 105-b, which may be an example of a basestation 105 described with reference to FIGS. 1-3. Process flow 400 mayalso illustrate aspects of techniques performed by a UE 115-b, which maybe an example of a UE 115 described with reference to FIGS. 1-3.

At 405, base station 105-b may identify a CSI-RS resource set with oneCSI-RS resource for transmission of multiple CSI-RSs to UE 115-b, wherethe CSI-RS resource is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial bandin a frequency domain, a time domain, or a combination thereof. Basestation 105-b may further identify a total number of precoderconfigurations for transmission of the multiple CSI-RSs, where theCSI-RS resource set may be partitioned into a plurality non-consecutivepartial bands based on the total number of precoder configurations.

At 410, base station 105-b may transmit one or both of the first partialband configuration or the second partial band configuration to a set ofUEs including UE 115-b. In some examples, the transmission of one orboth of the first partial band configuration and the second partial bandconfiguration may be performed via an RRC message, MAC channel element(CE), or via DCI.

At 415, base station 105-b may precode, according to a first precoderconfiguration, a first CSI-RS for transmission over a first resourcesubset of the CSI-RS resource associated with the first non-consecutivepartial band. Additionally, base station 105-a may precode, according toa second precoder configuration, a second CSI-RS for transmission over asecond resource subset of the CSI-RS resource associated with the secondnon-consecutive partial band. The first resource subset may span a timeinterval different from the second resource. UE 115-b may receive anindication of one or both of the first partial band configuration or thesecond partial band configuration. The indication may be received via anRRC message, MAC CE, or via DCI.

At 420, UE 115-b may receive, from base station 105-b, a first CSI-RSover the first resource subset of the CSI-RS resource associated withthe first non-consecutive partial band, where the first CSI-RS isprecoded according to a first precoder configuration. The first partialband configuration may indicate at least one of the first resourcesubset, a cycling granularity for the first non-consecutive partialband, a time interval for the first CSI-RS, a number of ports associatedwith transmission of the first CSI-RS, or a combination thereof. Thefirst cycling granularity for precoding the first non-consecutivepartial band may be equal to a second cycling granularity for precodingthe second non-consecutive partial band. The cycling granularity mayinclude a number of RBs in a frequency domain, time domain, or acombination thereof of the first resource subset. Base station 105-b maytransmit the precoded first CSI-RS.

Additionally, at 420, in some cases, the UE 115-b may receive, from basestation 105-b, a second CSI-RS over a second resource subset of theCSI-RS resource associated with a second non-consecutive partial band,where the second CSI-RS is precoded according to a second partial bandconfiguration. Base station 105-b may transmit the precoded secondCSI-RS using a part or all of the antenna ports in the set of antennaports. The transmission of the precoded first CSI-RS over the firstresource subset may occur at a different time than the transmission ofthe precoded second CSI-RS over the second non-consecutive partial band.Additionally, the first resource subset may span a time intervaldifferent from or the same as the second resource subset.

At 425, UE 115-b may determine, based on the first and second CSI-RSs,one or more channel state parameters for the CSI-RS resource. In somecases, the one or more channel state parameters may include at least oneof one or more of a CRI, a precoding matrix indicator, a precoding typeindicator, an RI, a CQI, or a combination thereof. In some cases, UE115-b may derive the channel state based on the average spectralefficiency of the first and second non-consecutive partial bands. UE115-b may calculate a spectral efficiency for the first or second CSI-RSbased on a co-phase vector associated with each RE of the first orsecond resource subset. Additionally, UE 115-b may estimate a channelmatrix for the first or second non-consecutive partial bandcorresponding to a beam matrix associated with each RB of the first orsecond resource subset.

At 430, UE 115-b may transmit, to base station 105-b, feedback messagethat indicates one or more channel state parameters. The one or morechannel state parameters may include at least one of a precoding matrixindicator, a precoding type indicator, an RI, a CQI, or a combinationthereof. Base station 105-b may receive the channel feedback messagefrom UE 115-b, where one or both of precoding the first CSI-RS orprecoding the second CSI-RS may be based on the channel feedbackmessage.

In some cases, base station 105-b may configure the CSI-RS resource setwith multiple CSI-RS resources, where each CSI-RS resource ispartitioned according to at least a first non-consecutive partial bandand a second non-consecutive partial band. At least two CSI-RS resourcesmay differ by at least a number of partial bands, a time duration foreach partial band, a cycling granularity for each partial band, a numberof CSI-RS ports for each partial band, precoder used for each partialband, or any combination thereof. Base station 105-b may transmit aCSI-RS resource set configuration to UE 105-b, where the CSI-RS resourceset configuration includes at least one of a number of CSI-RS resourcesof the CSI-RS resource set, a number of partial bands in each CSI-RSresource, a time duration for each partial band, a cycling granularityfor each partial band, a number of CSI-RS ports for each partial band,or a combination thereof. The configuration may be included in an RRCmessage, MAC CE, or in DCI. A format of the DCI may correspond to one ofa special DCI format or a CSI-RS DCI format. Additionally, the DCI maybe one of UE-specific or group-specific.

FIG. 5 shows a block diagram 500 of a wireless device 505 that supportspartial band configuration for channel state information in accordancewith aspects of the present disclosure. Wireless device 505 may be anexample of aspects of a base station 105 as described herein. Wirelessdevice 505 may include receiver 510, base station communications manager515, and transmitter 520. Wireless device 505 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

Receiver 510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to partial bandconfiguration for channel state information, etc.). Information may bepassed on to other components of the device. The receiver 510 may be anexample of aspects of the transceiver 835 described with reference toFIG. 8. The receiver 510 may utilize a single antenna or a set ofantennas.

Base station communications manager 515 may be an example of aspects ofthe base station communications manager 815 described with reference toFIG. 8.

Base station communications manager 515 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the base stationcommunications manager 515 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), an field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The base station communications manager 515 and/or at least some of itsvarious sub-components may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, base station communications manager 515and/or at least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station communications manager 515and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to aninput/output (I/O) component, a transceiver, a network server, anothercomputing device, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure.

Base station communications manager 515 may identify a CSI-RS resourceset for transmission of multiple CSI-RSs to a UE, where the CSI-RSresource set may have one or more CSI-RS resources, and each CSI-RSresource of the CSI-RS resource set is partitioned according to at leasta first non-consecutive partial band and a second non-consecutivepartial band in a frequency domain, time domain, or a combinationthereof. Base station communications manager 515 may precode, accordingto a first partial band configuration, a first CSI-RS for transmissionover a first resource subset of a CSI-RS resource associated with thefirst non-consecutive partial band, and precode, according to a secondpartial band configuration, a second CSI-RS for transmission over asecond resource subset of the a CSI-RS resource associated with thesecond non-consecutive partial band. Base station communications manager515 may transmit, to the UE, the precoded first CSI-RS over the firstresource subset and the precoded second CSI-RS using the second resourcesubset.

Transmitter 520 may transmit signals generated by other components ofthe device. In some examples, the transmitter 520 may be collocated witha receiver 510 in a transceiver module. For example, the transmitter 520may be an example of aspects of the transceiver 835 described withreference to FIG. 8. The transmitter 520 may utilize a single antenna ora set of antennas.

FIG. 6 shows a block diagram 600 of a wireless device 605 that supportspartial band configuration for channel state information in accordancewith aspects of the present disclosure. Wireless device 605 may be anexample of aspects of a wireless device 505 or a base station 105 asdescribed with reference to FIG. 5. Wireless device 605 may includereceiver 610, base station communications manager 615, and transmitter620. Wireless device 605 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to partial bandconfiguration for channel state information, etc.). Information may bepassed on to other components of the device. The receiver 610 may be anexample of aspects of the transceiver 835 described with reference toFIG. 8. The receiver 610 may utilize a single antenna or a set ofantennas.

Base station communications manager 615 may be an example of aspects ofthe base station communications manager 815 described with reference toFIG. 8. Base station communications manager 615 may also includeresource identifier 625, precoding component 630, and transmissioncomponent 635.

Resource identifier 625 may identify a CSI-RS resource set fortransmission of multiple CSI-RSs to a UE, where the CSI-RS resource setmay have one or more CSI-RS resources, and each CSI-RS resource of theCSI-RS resource set is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial bandin a frequency domain, time domain, or a combination thereof.

Precoding component 630 may precode, according to a first partial bandconfiguration, a first CSI-RS for transmission over a first resourcesubset of a CSI-RS resource associated with the first non-consecutivepartial band and precode, according to a second partial bandconfiguration, a second CSI-RS for transmission over a second resourcesubset of a CSI-RS resource associated with the second non-consecutivepartial band. In some cases, the first CSI-RS may be precoded accordingto a first precoder configuration, and the second CSI-RS may be precodedaccording to a second precoder configuration. In some examples, thefirst resource subset may span a time interval different from the secondresource subset. In some aspects, a first cycling granularity forprecoding the first non-consecutive partial band may be equal to ordifferent from a second cycling granularity for precoding the secondnon-consecutive partial band. In some cases, the first cyclinggranularity may be a parameter of the first partial band configuration,and the second cycling granularity may be a parameter of the secondpartial band configuration.

Transmission component 635 may transmit, to the UE, the precoded firstCSI-RS over the first resource subset and the precoded second CSI-RSusing the second resource subset. In some cases, the transmission of theprecoded first CSI-RS over the first resource subset may occur at adifferent time than the transmission of the precoded second CSI-RS overthe second non-consecutive partial band. In some examples, transmittingthe precoded first CSI-RS over the first resource subset may includetransmitting the precoded first CSI-RS using a part or all of theantenna ports in a set of antenna ports. In some aspects, transmittingthe precoded second CSI-RS over the second resource subset may includetransmitting the precoded second CSI-RS using a part or all of theantenna ports in the set of antenna ports.

Transmitter 620 may transmit signals generated by other components ofthe device. In some examples, the transmitter 620 may be collocated witha receiver 610 in a transceiver module. For example, the transmitter 620may be an example of aspects of the transceiver 835 described withreference to FIG. 8. The transmitter 620 may utilize a single antenna ora set of antennas.

FIG. 7 shows a block diagram 700 of a base station communicationsmanager 715 that supports partial band configuration for channel stateinformation in accordance with aspects of the present disclosure. Thebase station communications manager 715 may be an example of aspects ofa base station communications manager 515, a base station communicationsmanager 615, or a base station communications manager 815 described withreference to FIGS. 5, 6, and 8. The base station communications manager715 may include resource identifier 720, precoding component 725,transmission component 730, configuration component 735, receptioncomponent 740, and partial band component 745. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

Resource identifier 720 may identify a CSI-RS resource set fortransmission of multiple CSI-RSs to a UE, where the CSI-RS resource setmay have one or more CSI-RS resources, and each CSI-RS resource of theCSI-RS resource set is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial bandin a frequency domain, time domain, or a combination thereof.

Precoding component 725 may precode, according to a first partial bandconfiguration, a first CSI-RS for transmission over a first resourcesubset of a CSI-RS resource associated with the first non-consecutivepartial band and may precode, according to a second partial bandconfiguration, a second CSI-RS for transmission over a second resourcesubset of a CSI-RS resource associated with the second non-consecutivepartial band. In some cases, the first CSI-RS may be precoded accordingto a first precoder configuration, and the second CSI-RS may be precodedaccording to a second precoder configuration. In some examples, thefirst resource subset may span a time interval different from the secondresource subset. In some aspects, a first cycling granularity forprecoding the first non-consecutive partial band may be equal to ordifferent from a second cycling granularity for precoding the secondnon-consecutive partial band. In some instances, the first cyclinggranularity may be a parameter of the first partial band configuration,and the second cycling granularity may be a parameter of the secondpartial band configuration.

Transmission component 730 may transmit, to the UE, the precoded firstCSI-RS over the first resource subset and the precoded second CSI-RSusing the second resource subset. In some cases, the transmission of theprecoded first CSI-RS over the first resource subset may occur at adifferent time than the transmission of the precoded second CSI-RS overthe second non-consecutive partial band. In some examples, transmittingthe precoded first CSI-RS over the first resource subset may includetransmitting the precoded first CSI-RS using a part or all of theantenna ports in a set of antenna ports. In some instances, transmittingthe precoded second CSI-RS over the second resource subset may includetransmitting the precoded second CSI-RS using a part or all of theantenna ports in the set of antenna ports.

Configuration component 735 may identify a total number of precoderconfigurations for transmission of multiple CSI-RSs in a CSI-RSresource, where the CSI-RS resource is partitioned into a setnon-consecutive partial bands based on the total number of precoderconfigurations.

Reception component 740 may receive a channel feedback message from theUE, where one or both of precoding the first CSI-RS or precoding thesecond CSI-RS is based on the channel feedback message. In some cases,the channel feedback message may indicate at least one of one or moreCRI, a precoding matrix indicator, a preceding type indicator, an RI, aCQI, or a combination thereof.

Partial band component 745 may transmit one or both of the first partialband configuration or the second partial band configuration to a set ofUEs including the UE. In some cases, the transmission of one or both ofthe first partial band configuration and the second partial bandconfiguration may be via an RRC message, MAC CE, or via DCI. In somecases, the transmission the first partial band configuration and thesecond partial band configuration may be individually or jointly encodedin DCI. In some examples, a format of the DCI may correspond to one of aspecial DCI format or a CSI-RS DCI format. In some instances, the DCImay be one of UE-specific or group-specific.

FIG. 8 shows a diagram of a system 800 including a device 805 thatsupports partial band configuration for channel state information inaccordance with aspects of the present disclosure. Device 805 may be anexample of or include the components of wireless device 505, wirelessdevice 605, or a base station 105 as described above, e.g., withreference to FIGS. 5 and 6. Device 805 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including base stationcommunications manager 815, processor 820, memory 825, software 830,transceiver 835, antenna 840, network communications manager 845, andinter-station communications manager 850. These components may be inelectronic communication via one or more buses (e.g., bus 810). Device805 may communicate wirelessly with one or more UEs 115.

Processor 820 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, processor 820 maybe configured to operate a memory array using a memory controller. Inother cases, a memory controller may be integrated into processor 820.Processor 820 may be configured to execute computer-readableinstructions stored in a memory to perform various functions (e.g.,functions or tasks supporting partial band configuration for channelstate information).

Memory 825 may include random access memory (RAM) and read only memory(ROM). The memory 825 may store computer-readable, computer-executablesoftware 830 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 825 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware or software operationsuch as the interaction with peripheral components or devices.

Software 830 may include code to implement aspects of the presentdisclosure, including code to support partial band configuration forchannel state information. Software 830 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 830 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 835 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 835 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 835may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas.

In some cases, the wireless device may include a single antenna 840.However, in some cases the device may have more than one antenna 840,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

Network communications manager 845 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 845 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Inter-station communications manager 850 may manage communications withother base station 105, and may include a controller or scheduler forcontrolling communications with UEs 115 in cooperation with other basestations 105. For example, the inter-station communications manager 850may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, inter-station communications manager 850may provide an X2 interface within an LTE/LTE-A wireless communicationnetwork technology to provide communication between base stations 105.

FIG. 9 shows a block diagram 900 of a wireless device 905 that supportspartial band configuration for channel state information in accordancewith aspects of the present disclosure. Wireless device 905 may be anexample of aspects of a UE 115 as described herein. Wireless device 905may include receiver 910, UE communications manager 915, and transmitter920. Wireless device 905 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to partial bandconfiguration for channel state information, etc.). Information may bepassed on to other components of the device. The receiver 910 may be anexample of aspects of the transceiver 1235 described with reference toFIG. 12. The receiver 910 may utilize a single antenna or a set ofantennas.

UE communications manager 915 may be an example of aspects of the UEcommunications manager 1215 described with reference to FIG. 12.

UE communications manager 915 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the UE communicationsmanager 915 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a DSP, an ASIC, an FPGA orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described in the present disclosure.

The UE communications manager 915 and/or at least some of its varioussub-components may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE communications manager 915 and/or at least some of itsvarious sub-components may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE communications manager 915 and/or at least some of itsvarious sub-components may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

UE communications manager 915 may receive, from a base station, a firstCSI-RS over a first resource subset of a CSI-RS resource associated witha first non-consecutive partial band, where the first CSI-RS is precodedaccording to a first partial band configuration. UE communicationsmanager 915 may receive a second CSI-RS over a second resource subset ofthe CSI-RS resource associated with a second non-consecutive partialband, where the second CSI-RS is precoded according to a second partialband configuration. UE communications manager 915 may determine, basedon the first and second CSI-RSs, one or more channel state parametersfor the CSI-RS resource, and transmit, to the base station, a feedbackmessage that indicates the channel state parameters. The CSI-RS resourcemay include one CSI-RS resource of a CSI-RS resource set.

In some cases, UE communications manager 915 may receive, from the basestation, multiple CSI-RS resources from the CSI-RS resource set, whereeach CSI-RS resource is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial band.At least two CSI-RS resources may differ by at least a number of partialbands, a time duration for each partial band, a cycling granularity foreach partial band, a number of CSI-RS ports for each partial band,precoder used for each partial band, or any combination thereof.Further, UE communications manager 915 may receive, from the basestation, a CSI-RS resource set configuration, where the CSI-RS resourceset configuration includes at least one of a number of CSI-RS resourcesof the CSI-RS resource set, a number of partial bands in each CSI-RSresource, a time duration for each partial band, a cycling granularityfor each partial band, a number of CSI-RS ports for each partial band,or a combination thereof. The configuration may be included in an RRCmessage, MAC CE, or in DCI. The feedback message may be generated basedon a measurement and computation of each CSI-RS resource.

Transmitter 920 may transmit signals generated by other components ofthe device. In some examples, the transmitter 920 may be collocated witha receiver 910 in a transceiver module. For example, the transmitter 920may be an example of aspects of the transceiver 1235 described withreference to FIG. 12. The transmitter 920 may utilize a single antennaor a set of antennas.

FIG. 10 shows a block diagram 1000 of a wireless device 1005 thatsupports partial band configuration for channel state information inaccordance with aspects of the present disclosure. Wireless device 1005may be an example of aspects of a wireless device 905 or a UE 115 asdescribed with reference to FIG. 9. Wireless device 1005 may includereceiver 1010, UE communications manager 1015, and transmitter 1020.Wireless device 1005 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 1010 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to partial bandconfiguration for channel state information, etc.). Information may bepassed on to other components of the device. The receiver 1010 may be anexample of aspects of the transceiver 1235 described with reference toFIG. 12. The receiver 1010 may utilize a single antenna or a set ofantennas.

UE communications manager 1015 may be an example of aspects of the UEcommunications manager 1215 described with reference to FIG. 12. UEcommunications manager 1015 may also include reception component 1025,channel state component 1030, and transmission component 1035.

Reception component 1025 may receive, from a base station, a firstCSI-RS over a first resource subset of a CSI-RS resource associated witha first non-consecutive partial band, where the first CSI-RS is precodedaccording to a first partial band configuration, and may receive asecond CSI-RS over a second resource subset of the CSI-RS resource setassociated with a second non-consecutive partial band, where the secondCSI-RS is precoded according to a second partial band configuration. TheCSI-RS resource may include one CSI-RS resource of a CSI-RS resourceset.

In some cases, reception component 1025 may receive, from the basestation, multiple CSI-RS resources from the CSI-RS resource set, whereeach CSI-RS resource is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial band.At least two CSI-RS resources may differ by at least a number of partialbands, a time duration for each partial band, a cycling granularity foreach partial band, a number of CSI-RS ports for each partial band,precoder used for each partial band, or any combination thereof.Further, reception component 1025 may receive, from the base station, aCSI-RS resource set configuration, where the CSI-RS resource setconfiguration includes at least one of a number of CSI-RS resources ofthe CSI-RS resource set, a number of partial bands in each CSI-RSresource, a time duration for each partial band, a cycling granularityfor each partial band, a number of CSI-RS ports for each partial band,or a combination thereof. The configuration may be included in a RRCmessage, MAC CE, or in DCI.

Channel state component 1030 may determine, based on the first andsecond CSI-RSs, one or more channel state parameters for the CSI-RSresource. In some cases, the one or more channel state parameters mayinclude at least one of one or more CRI, a precoding matrix indicator, aprecoding type indicator, an RI, a CQI, or a combination thereof.

Transmission component 1035 may transmit, to the base station, afeedback message that indicates the channel state parameter.

Transmitter 1020 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1020 may be collocatedwith a receiver 1010 in a transceiver module. For example, thetransmitter 1020 may be an example of aspects of the transceiver 1235described with reference to FIG. 12. The transmitter 1020 may utilize asingle antenna or a set of antennas.

FIG. 11 shows a block diagram 1100 of a UE communications manager 1115that supports partial band configuration for channel state informationin accordance with aspects of the present disclosure. The UEcommunications manager 1115 may be an example of aspects of a UEcommunications manager 1215 described with reference to FIGS. 9, 10, and12. The UE communications manager 1115 may include reception component1120, channel state component 1125, transmission component 1130,configuration component 1135, spectral component 1140, and channelestimator 1145. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

Reception component 1120 may receive, from a base station, a firstCSI-RS over a first resource subset of a CSI-RS resource associated witha first non-consecutive partial band, where the first CSI-RS is precodedaccording to a first partial band configuration, and may receive asecond CSI-RS over a second resource subset of the CSI-RS resourceassociated with a second non-consecutive partial band, where the secondCSI-RS is precoded according to a second partial band configuration. TheCSI-RS resource may include one CSI-RS resource of a CSI-RS resourceset.

In some cases, reception component 1120 may receive, from the basestation, multiple CSI-RS resources from the CSI-RS resource set, whereeach CSI-RS resource is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial band.At least two CSI-RS resources may differ by at least a number of partialbands, a time duration for each partial band, a cycling granularity foreach partial band, a number of CSI-RS ports for each partial band,precoder used for each partial band, or any combination thereof.Further, the reception component 1120 may receive, from the basestation, a CSI-RS resource set configuration, where the CSI-RS resourceset configuration includes at least one of a number of CSI-RS resourcesof the CSI-RS resource set, a number of partial bands in each CSI-RSresource, a time duration for each partial band, a cycling granularityfor each partial band, a number of CSI-RS ports for each partial band,or a combination thereof. The configuration may be included in an RRCmessage, MAC CE, or in DCI.

Channel state component 1125 may determine, based on the first andsecond CSI-RSs, one or more channel state parameters for the CSI-RSresource. In some examples, the one or more channel state parameters mayinclude at least one of one or more CRI, a precoding matrix indicator, aprecoding type indicator, an RI, a CQI, or a combination thereof.

Transmission component 1130 may transmit, to the base station, afeedback message that indicates the channel state parameter.

Configuration component 1135 may receive, from the base station, anindication of one or both of the first partial band configuration or thesecond partial band configuration. In some cases, the indication may bereceived via an RRC message, MAC CE, or via DCI. In some examples, thefirst partial band configuration may indicate at least one of the firstresource subset, a first cycling granularity for the firstnon-consecutive partial band, a first time interval for the firstCSI-RS, a first number of ports associated with transmission of thefirst CSI-RS, or a combination thereof. In some aspects, the secondpartial band configuration may indicate at least one of the secondresource subset, a second cycling granularity for the secondnon-consecutive partial band, a second time interval for the secondCSI-RS, a second number of ports associated with transmission of thesecond CSI-RS, or a combination thereof. In some instances, the firstcycling granularity may indicate a number of RBs of the first resourcesubset. In some cases, the second cycling granularity may indicate anumber of RBs of the second resource subset.

Spectral component 1140 may calculate a first spectral efficiency forthe first CSI-RS based on a first CSI-RS port to data precoder mappingand may calculate a second spectral efficiency for the second CSI-RSbased on a second CSI-RS port to data precoder mapping. In some cases,one or both of the first and second CSI-RS port to data precodermappings may be based in part on a co-phase vector associated with a setof REs corresponding to a respective resource subset of the firstresource subset and the second resource subset.

Channel estimator 1145 may estimate a first effective channel for thefirst non-consecutive partial band based on a first set of RBs of thefirst resource subset and may estimate a second effective channel forthe second non-consecutive partial band based on a second set of RBs ofthe second resource subset.

FIG. 12 shows a diagram of a system 1200 including a device 1205 thatsupports partial band configuration for channel state information inaccordance with aspects of the present disclosure. Device 1205 may be anexample of or include the components of UE 115 as described above, e.g.,with reference to FIG. 1. Device 1205 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including UE communicationsmanager 1215, processor 1220, memory 1225, software 1230, transceiver1235, antenna 1240, and I/O controller 1245. These components may be inelectronic communication via one or more buses (e.g., bus 1210). Device1205 may communicate wirelessly with one or more base stations 105.

Processor 1220 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 1220 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 1220. Processor 1220 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting partial bandconfiguration for channel state information).

Memory 1225 may include RAM and ROM. The memory 1225 may storecomputer-readable, computer-executable software 1230 includinginstructions that, when executed, cause the processor to perform variousfunctions described herein. In some cases, the memory 1225 may contain,among other things, a BIOS which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

Software 1230 may include code to implement aspects of the presentdisclosure, including code to support partial band configuration forchannel state information. Software 1230 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 1230 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 1235 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1235 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1235 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1240.However, in some cases the device may have more than one antenna 1240,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

I/O controller 1245 may manage input and output signals for device 1205.I/O controller 1245 may also manage peripherals not integrated intodevice 1205. In some cases, I/O controller 1245 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 1245 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem. In other cases, I/O controller 1245 may represent or interactwith a modem, a keyboard, a mouse, a touchscreen, or a similar device.In some cases, I/O controller 1245 may be implemented as part of aprocessor. In some cases, a user may interact with device 1205 via I/Ocontroller 1245 or via hardware components controlled by I/O controller1245.

FIG. 13 shows a flowchart illustrating a method 1300 for partial bandconfiguration for channel state information in accordance with aspectsof the present disclosure. The operations of method 1300 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1300 may be performed by a basestation communications manager as described with reference to FIGS. 5through 8. In some examples, a base station 105 may execute a set ofcodes to control the functional elements of the device to perform thefunctions described below. Additionally or alternatively, the basestation 105 may perform aspects of the functions described below usingspecial-purpose hardware.

At 1305, the base station 105 may identify a CSI-RS resource set fortransmission of multiple CSI-RSs to a UE, where the CSI-RS resource setmay have one or more CSI-RS resources, and each CSI-RS resource of theCSI-RS resource set is partitioned according to at least a firstnon-consecutive partial band and a second non-consecutive partial bandin a frequency domain, time domain, or a combination thereof. Theoperations of block 1305 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1305may be performed by a resource identifier as described with reference toFIGS. 5 through 8.

At 1310, the base station may transmit a control message indicating aconfiguration for the first non-consecutive partial band and the secondnon-consecutive partial band in the frequency domain, time domain, or acombination thereof. The operations of 1310 may be performed accordingto the methods described herein. In certain examples, aspects of theoperations of 1310 may be performed by a resource identifier asdescribed with reference to FIGS. 5 through 8.

At 1315, the base station 105 may precode, according to a first partialband configuration, a first CSI-RS for transmission over a firstresource subset of the CSI-RS resource associated with the firstnon-consecutive partial band. The operations of 1315 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1315 may be performed by a precoding component asdescribed with reference to FIGS. 5 through 8. Additionally, the basestation 105 may precode, according to a second partial bandconfiguration, a second CSI-RS for transmission over a second resourcesubset of the CSI-RS resource set associated with the secondnon-consecutive partial band. The operations of 1315 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1315 may be performed by a precoding component asdescribed with reference to FIGS. 5 through 8.

At 1320, the base station 105 may transmit, to the UE, the precodedfirst CSI-RS over the first resource subset and the precoded secondCSI-RS using the second resource subset. The operations of 1320 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1320 may be performed by atransmission component as described with reference to FIGS. 5 through 8.

FIG. 14 shows a flowchart illustrating a method 1400 for partial bandconfiguration for channel state information in accordance with aspectsof the present disclosure. The operations of method 1400 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1400 may be performed by a UEcommunications manager as described with reference to FIGS. 9 through12. In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At 1405, the UE 115 may receive, from a base station, a first partialband configuration and a second partial band configuration via a controlmessage. The operations of 1405 may be performed according to themethods described herein. In certain examples, aspects of the operationsof 1405 may be performed by a reception component as described withreference to FIGS. 9 through 12.

At 1410, the UE 115 may receive, from a base station, a first CSI-RSover a first resource subset of a CSI-RS resource associated with afirst non-consecutive partial band, where the first CSI-RS is precodedaccording to the first partial band configuration. The operations of1410 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1410 may be performed bya reception component as described with reference to FIGS. 9 through 12.Additionally, the UE 115 may receive a second CSI-RS over a secondresource subset of the CSI-RS resource associated with a secondnon-consecutive partial band, where the second CSI-RS is precodedaccording to the second partial band configuration. The operations of1410 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1410 may be performed bya reception component as described with reference to FIGS. 9 through 12.

At 1415, the UE 115 may determine, based on the first and secondCSI-RSs, one or more channel state parameters for the CSI-RS resource.The operations of 1415 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1415may be performed by a channel state component as described withreference to FIGS. 9 through 12.

At 1420, the UE 115 may transmit, to the base station, a feedbackmessage that indicates the channel state parameters. The operations of1420 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1420 may be performed bya transmission component as described with reference to FIGS. 9 through12.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.The terms “system” and “network” are often used interchangeably. A codedivision multiple access (CDMA) system may implement a radio technologysuch as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc.CDMA2000 covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releasesmay be commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE and LTE-A are releases of UMTSthat use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, NR, and GSM aredescribed in documents from the organization named “3rd GenerationPartnership Project” (3GPP). CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the systems andradio technologies mentioned above as well as other systems and radiotechnologies. While aspects of an LTE or an NR system may be describedfor purposes of example, and LTE or NR terminology may be used in muchof the description, the techniques described herein are applicablebeyond LTE or NR applications.

In LTE/LTE-A networks, including such networks described herein, theterm evolved node B (eNB) may be generally used to describe the basestations. The wireless communications system or systems described hereinmay include a heterogeneous LTE/LTE-A or NR network in which differenttypes of eNBs provide coverage for various geographical regions. Forexample, each eNB, next generation NodeB (gNB), or base station mayprovide communication coverage for a macro cell, a small cell, or othertypes of cell. The term “cell” may be used to describe a base station, acarrier or component carrier associated with a base station, or acoverage area (e.g., sector, etc.) of a carrier or base station,depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), gNB, Home NodeB, aHome eNodeB, or some other suitable terminology. The geographic coveragearea for a base station may be divided into sectors making up only aportion of the coverage area. The wireless communications system orsystems described herein may include base stations of different types(e.g., macro or small cell base stations). The UEs described herein maybe able to communicate with various types of base stations and networkequipment including macro eNBs, small cell eNBs, gNBs, relay basestations, and the like. There may be overlapping geographic coverageareas for different technologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers).

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The downlink transmissions described herein may also be called forwardlink transmissions while the uplink transmissions may also be calledreverse link transmissions. Each communication link describedherein—including, for example, wireless communications system 100 and200 of FIGS. 1 and 2—may include one or more carriers, where eachcarrier may be a signal made up of multiple sub-carriers (e.g., waveformsignals of different frequencies).

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more of”) indicates an inclusivelist such that, for example, a list of at least one of A, B, or C meansA or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, asused herein, the phrase “based on” shall not be construed as a referenceto a closed set of conditions. For example, an exemplary step that isdescribed as “based on condition A” may be based on both a condition Aand a condition B without departing from the scope of the presentdisclosure. In other words, as used herein, the phrase “based on” shallbe construed in the same manner as the phrase “based at least in parton.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media maycomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

1. A method for wireless communication, comprising: identifying achannel state information reference signal (CSI-RS) resource set withone CSI-RS resource for transmission of multiple CSI-RSs to a userequipment (UE); precoding, according to a first partial bandconfiguration, a first CSI-RS for transmission over a first resourcesubset of the CSI-RS resource associated with a first non-consecutivepartial band; precoding, according to a second partial bandconfiguration, a second CSI-RS for transmission over a second resourcesubset of the CSI-RS resource associated with a second non-consecutivepartial band; and transmitting, to the UE, the precoded first CSI-RSover the first resource subset and the precoded second CSI-RS over thesecond resource subset.
 2. The method of claim 1, wherein: the CSI-RSresource is partitioned according to at least the first non-consecutivepartial band and the second non-consecutive partial band in a frequencydomain, or time domain, or a combination thereof.
 3. The method of claim1, wherein: the first CSI-RS is precoded according to a first precoderconfiguration and the second CSI-RS is precoded according to a secondprecoder configuration.
 4. The method of claim 1, further comprising:identifying a total number of precoder configurations for transmissionof the multiple CSI-RSs, wherein the CSI-RS resource is partitioned intoa plurality non-consecutive partial bands based at least in part on thetotal number of precoder configurations.
 5. The method of claim 1,further comprising: receiving a channel feedback message from the UE,wherein the channel feedback message is computed based on one or both ofthe first precoded CSI-RS and the second precoded CSI-RS, and whereinthe channel feedback message indicates at least one of a precodingmatrix indicator, a precoding type indicator, a rank indicator, achannel quality indicator, or a combination thereof.
 6. (canceled) 7.The method of claim 1, wherein: the transmission of the precoded firstCSI-RS over the first resource subset of the CSI-RS resource associatedwith the first non-consecutive partial band occurs at a different timethan or at a same time as the transmission of the precoded second CSI-RSover the second resource subset of the CSI-RS resource associated withthe second non-consecutive partial band.
 8. The method of claim 1,wherein: the first resource subset spans a time interval different fromor the same as the second resource subset.
 9. The method of claim 1,wherein: a first cycling granularity for precoding the first CSI-RS forthe first non-consecutive partial band is equal to or different from asecond cycling granularity for precoding the second CSI-RS for thesecond non-consecutive partial bands, and wherein the first cyclinggranularity is a parameter of the first partial band configuration andthe second cycling granularity is a parameter of the second partial bandconfiguration.
 10. (canceled)
 11. The method of claim 1, wherein:transmitting the precoded first CSI-RS over the first resource subsetcomprises: transmitting the precoded first CSI-RS using a part or allantenna ports in a set of antenna ports; and wherein transmitting theprecoded second CSI-RS over the second resource subset comprises:transmitting the precoded second CSI-RS using a art or all antenna portsin the set of antenna ports.
 12. (canceled)
 13. The method of claim 1,further comprising: configuring the CSI-RS resource set with multipleCSI-RS resources, wherein each CSI-RS resource is partitioned accordingto at least the first non-consecutive partial band and the secondnon-consecutive partial band, and wherein at least two CSI-RS resourcesare different by at least a number of partial bands, a time duration foreach partial band, a cycling granularity for each partial band, a numberof CSI-RS ports for each partial band, precoder used for each partialband, or any combination thereof.
 14. (canceled)
 15. The method of claim1, further comprising: transmitting a CSI-RS resource set configurationto the UE, wherein the CSI-RS resource set configuration comprises atleast one of a number of CSI-RS resources of the CSI-RS resource set, anumber of partial bands in each CSI-RS resource, a time duration foreach partial band, a cycling granularity for each partial band, a numberof CSI-RS ports for each partial band, or a combination thereof.
 16. Themethod of claim 15, wherein: the configuration is included in a radioresource control (RRC) message, medium access control (MAC) channelelement (CE), or in downlink control information (DCI).
 17. The methodof claim 15, wherein: the transmission the first partial bandconfiguration and the second partial band configuration are individuallyor jointly encoded in DCI.
 18. The method of claim 17, wherein: a formatof the DCI corresponds to one of a special DCI format or a CSI-RS DCIformat.
 19. The method of claim 17, wherein: the DCI is one ofUE-specific or group-specific.
 20. The method of claim 13, furthercomprising: receiving a channel feedback message from the UE, whereinthe channel feedback message is computed based on at least one of theCSI-RS resources of the CSI-RS resource set, and wherein the channelfeedback message indicates at least one of one or more CSI-RS resourceindication (CRI), a precoding matrix indicator, a precoding typeindicator, a rank indicator, a channel quality indicator, or acombination thereof.
 21. (canceled)
 22. A method for wirelesscommunication, comprising: receiving, from a base station, a firstchannel state information reference signal (CSI-RS) over a firstresource subset of a CSI-RS resource associated with a firstnon-consecutive partial band, wherein the first CSI-RS is precodedaccording to a first partial band configuration; receiving a secondCSI-RS over a second resource subset of the CSI-RS resource associatedwith a second non-consecutive partial band, wherein the second CSI-RS isprecoded according to a second partial band configuration; determining,based at least in part on the first and second CSI-RSs, a channel stateparameter based at least in part on the first non-consecutive partialband and the second non-consecutive partial band; and transmitting, tothe base station, a feedback message that indicates the channel stateparameter.
 23. The method of claim 22, wherein: determining the channelstate parameter comprises: determining one or more channel stateparameters for the CSI-RS resource corresponding to the first and secondnon-consecutive partial bands based at least in part on a channelestimation of the first and second non-consecutive partial bands. 24.The method of claim 22, further comprising: receiving, from the basestation, an indication of one or both of the first partial bandconfiguration or the second partial band configuration, wherein theindication is received via a radio resource control (RRC) message,medium access control (MAC) channel element (CE), or downlink controlinformation (DCI).
 25. (canceled)
 26. The method of claim 22, wherein:the first CSI-RS precoder configuration indicates at least one of thefirst resource subset, a first cycling granularity for the firstnon-consecutive partial band, a first time interval for the firstCSI-RS, a first number of ports associated with transmission of thefirst CSI-RS, or a combination thereof; and the second CSI-RS precoderconfiguration indicates at least one of the second resource subset, asecond cycling granularity for the second non-consecutive partial band,a second time interval for the second CSI-RS, a second number of portsassociated with transmission of the second CSI-RS, or a combinationthereof.
 27. The method of claim 26, wherein: the first cyclinggranularity indicates a number of consecutive resource blocks (RBs) in afrequency domain, time domain, or a combination thereof of the firstresource subset; and the second cycling granularity indicates a numberof consecutive resource blocks (RBs) in a frequency domain, a timedomain, or a combination thereof of the second resource subset.
 28. Themethod of claim 22, further comprising: estimating a first effectivechannel for the first non-consecutive partial band based at least inpart on a first set of RBs of the first resource subset; and estimatinga second effective channel for the second non-consecutive partial bandbased at least in part on a second set of RBs of the second resourcesubset, wherein the second non-consecutive partial band comprises anon-consecutive partial band from the first non-consecutive partial bandin a frequency domain, time domain, or a combination thereof.
 29. Themethod of claim 28, further comprising: selecting a channel stateinformation resource indicator (CRI) based at least in part on the firstand second effective channels, wherein the channel state parameter isdetermined based at least in part on the CRI, and wherein the channelstate parameter comprises at least one of a precoding matrix indicator,a precoding type indicator, a rank indicator, a channel qualityindicator, or a combination thereof.
 30. (canceled)
 31. The method ofclaim 26, wherein: one or both of a first and second CSI-RS port to dataprecoder mappings is based in part on a co-phase vector or Alamoutiencoding associated with a set of resource elements (REs) correspondingto a respective resource subset of the first resource subset and thesecond resource subset.
 32. The method of claim 22, further comprising:receiving, from the base station, a control message indicating that thefirst partial band configuration and the second partial bandconfiguration have different configuration parameters, wherein at leastone configuration parameter of the first partial band configuration orthe second partial band configuration is received in a radio resourcecontrol (RRC) message, medium access control (MAC) channel element (CE),or in downlink control information (DCI).
 33. (canceled)
 34. The methodof claim 22, wherein: the CSI-RS resource comprises one CSI-RS resourceof a CSI-RS resource set.
 35. The method of claim 22, furthercomprising: receiving, from the base station, multiple CSI-RS resourcesfrom the CSI-RS resource set, wherein each CSI-RS resource ispartitioned according to at least the first non-consecutive partial bandand the second non-consecutive partial band, and wherein at least twoCSI-RS resources are different by at least a number of partial bands atime duration for each partial band, a cycling granularity for eachpartial band, a number of CSI-RS ports for each partial band, precoderused for each partial band, or any combination thereof.
 36. (canceled)37. The method of claim 22, further comprising: receiving, from the basestation, a CSI-RS resource set configuration, wherein the CSI-RSresource set configuration comprises at least one of a number of CSI-RSresources of the CSI-RS resource set, a number of partial bands in eachCSI-RS resource, a time duration for each partial band, a cyclinggranularity for each partial band, a number of CSI-RS ports for eachpartial band, or a combination thereof, and wherein the configuration isincluded in a radio resource control (RRC) message, medium accesscontrol (MAC) channel e element (CE), or in downlink control Information(DCI). 38-76. (canceled)
 77. An apparatus for wireless communication,comprising: a processor; memory in electronic communication with theprocessor; and instructions stored in the memory and operable, whenexecuted by the processor, to cause the apparatus to: identify a channelstate information reference signal (CSI-RS) resource set with one CSI-RSresource for transmission of multiple CSI-RSs to a user equipment (UE);precode, according to a first partial band configuration, a first CSI-RSfor transmission over a first resource subset of the CSI-RS resourceassociated with a first non-consecutive partial band; precode, accordingto a second partial band configuration, a second CSI-RS for transmissionover a second resource subset of the CSI-RS resource associated with asecond non-consecutive partial band; and transmit, to the UE, theprecoded first CSI-RS over the first resource subset and the precodedsecond CSI-RS over the second resource subset. 78-97. (canceled)
 98. Anapparatus for wireless communication, comprising: a processor; memory inelectronic communication with the processor; and instructions stored inthe memory and operable, when executed by the processor, to cause theapparatus to: receive, from a base station, a first channel stateinformation reference signal (CSI-RS) over a first resource subset of aCSI-RS resource associated with a first non-consecutive partial band,wherein the first CSI-RS is precoded according to a first partial bandconfiguration; receive a second CSI-RS over a second resource subset ofthe CSI-RS resource associated with a second non-consecutive partialband, wherein the second CSI-RS is precoded according to a secondpartial band configuration; determine, based at least in part on thefirst and second CSI-RSs, a channel state parameter based at least inpart on the first non-consecutive partial band and the secondnon-consecutive partial band; and transmit, to the base station, afeedback message that indicates the channel state parameter. 99-152.(canceled)